SOLUTION: Determine the equation for the directrix of the parabola y = 1/16 x2 Be sure to write your answer as an equation for a line

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Question 876026: Determine the equation for the directrix of the parabola y = 1/16 x2
Be sure to write your answer as an equation for a line
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
y = (1/16)x^2
1/(4p) = 1/16, p = 4
With Directrix y = (k - p) 0r y = (0-p)
y = -4, the Directrix
Need to Know:
the vertex form of a Parabola opening up(a>0) or down(a<0), y=a%28x-h%29%5E2+%2Bk
where(h,k) is the vertex and x = h is the Line of Symmetry
The standard form is %28x+-h%29%5E2+=+4p%28y+-k%29, 0r a = 1/4p, where the focus is (h,k + p)
With Directrix y = (k - p)